MySQL Cluster NDB 7.1.25 was withdrawn shortly after release,
due to a problem with primary keys and tables with very many
rows that was introduced in this release (Bug #16023068, Bug
#67928). Users should upgrade to MySQL Cluster NDB 7.1.26,
which fixes this issue.

MySQL Cluster NDB 7.1.25 is a new release of MySQL Cluster,
incorporating new features in the
NDB storage engine and fixing
recently discovered bugs in previous MySQL Cluster NDB 7.1
releases.

This release also incorporates all bugfixes and changes made in
previous MySQL Cluster releases, as well as all bugfixes and
feature changes which were added in mainline MySQL 5.1 through
MySQL 5.1.66 (see Changes in MySQL 5.1.66 (2012-09-28)).

Added 3 new columns to the
transporters table in the
ndbinfo database. The
remote_address,
bytes_sent, and
bytes_received columns help to provide an
overview of data transfer across the transporter links in a
MySQL Cluster. This information can be useful in verifying
system balance, partitioning, and front-end server load
balancing; it may also be of help when diagnosing network
problems arising from link saturation, hardware faults, or other
causes.
(Bug #14685458)

Data node logs now provide tracking information about
arbitrations, including which nodes have assumed the arbitrator
role and at what times.
(Bug #11761263, Bug #53736)

Bugs Fixed

A slow filesystem during local checkpointing could exert undue
pressure on DBDIH kernel block file page
buffers, which in turn could lead to a data node crash when
these were exhausted. This fix limits the number of table
definition updates that DBDIH can issue
concurrently.
(Bug #14828998)

The management server process, when started with
--config-cache=FALSE, could
sometimes hang during shutdown.
(Bug #14730537)

The output from ndb_config--configinfo now contains the
same information as that from ndb_config--configinfo--xml, including explicit
indicators for parameters that do not require restarting a data
node with --initial to take effect.
In addition, ndb_config indicated incorrectly
that the
LogLevelCheckpoint data
node configuration parameter requires an initial node restart to
take effect, when in fact it does not; this error was also
present in the MySQL Cluster documentation, where it has also
been corrected.
(Bug #14671934)

Concurrent ALTER TABLE with other
DML statements on the same NDB table returned Got
error -1 'Unknown error code' from NDBCLUSTER.
(Bug #14578595)

CPU consumption peaked several seconds after the forced
termination an NDB client application due to the fact that the
DBTC kernel block waited for any open transactions owned by the
disconnected API client to be terminated in a busy loop, and did
not break between checks for the correct state.
(Bug #14550056)

Added the --connect-retries and
--connect-delay startup options for
ndbd and ndbmtd.
--connect-retries (default 12) controls how
many times the data node tries to connect to a management server
before giving up; setting it to -1 means that the data node
never stops trying to make contact.
--connect-delay sets the number of seconds to
wait between retries; the default is 5.
(Bug #14329309, Bug #66550)

Following a failed
ALTER
TABLE ... REORGANIZE PARTITION statement, a subsequent
execution of this statement after adding new data nodes caused a
failure in the DBDIH kernel block which led
to an unplanned shutdown of the cluster.

DUMP code 7019 was added as part of this fix.
It can be used to obtain diagnostic information relating to a
failed data node. See
DUMP 7019, for more
information.
(Bug #14220269)

References: See also: Bug #18550318.

It was possible in some cases for two transactions to try to
drop tables at the same time. If the master node failed while
one of these operations was still pending, this could lead
either to additional node failures (and cluster shutdown) or to
new dictionary operations being blocked. This issue is addressed
by ensuring that the master will reject requests to start or
stop a transaction while there are outstanding dictionary
takeover requests. In addition, table-drop operations now
correctly signal when complete, as the DBDICT
kernel block could not confirm node takeovers while such
operations were still marked as pending completion.
(Bug #14190114)

The DBSPJ kernel block had no information
about which tables or indexes actually existed, or which had
been modified or dropped, since execution of a given query
began. Thus, DBSPJ might submit dictionary
requests for nonexistent tables or versions of tables, which
could cause a crash in the DBDIH kernel
block.

This fix introduces a simplified dictionary into the
DBSPJ kernel block such that
DBSPJ can now check reliably for the
existence of a particular table or version of a table on which
it is about to request an operation.
(Bug #14103195)

Previously, it was possible to store a maximum of 46137488 rows
in a single MySQL Cluster partition. This limitation has now
been removed.
(Bug #13844405, Bug #14000373)

References: See also: Bug #13436216.

When using ndbmtd and performing joins, data
nodes could fail where ndbmtd processes were
configured to use a large number of local query handler threads
(as set by the
ThreadConfig
configuration parameter), the tables accessed by the join had a
large number of partitions, or both.
(Bug #13799800, Bug #14143553)

Cluster Replication:
When the value of
ndb_log_apply_status was set to
1, it was theoretically possible for the
ndb_apply_status table's
server_id column not to be propagated
correctly.
(Bug #14772503)

Cluster Replication:
Transactions originating on a replication master are applied on
slaves as if using AO_AbortError, but
transactions replayed from a binary log were not. Now
transactions being replayed from a log are handled in the same
way as those coming from a “live” replication
master.